How efficient are wind turbines?
Modern wind turbines are operational for 70-85% of the time and over the course of the year they will generate, on average, up to 35% of the theoretical maximum output (i). This is known as a load or capacity factor. The exact figure is dependant on the location, technology, size, turbine reliability and wind conditions. By comparison, the load factor of conventional power stations is on average 50% (ii).
The theoretical maximum energy that a wind turbine can extract from the wind impinging upon it is around 60%. However the meaning of efficiency is different with wind energy, where the fuel is free. The primary concern is not the efficiency for its own sake, but to improve productivity in order to bring down the price of wind energy.
The theoretical maximum energy which a wind turbine can extract from the wind blowing across it is just under 60%, known as the Betz limit. However the meaning of efficiency is a redundant concept to apply to wind energy, where the fuel is free. The primary concern is not the efficiency for its own sake, but to improve productivity in order to bring the price of wind energy down. People often confuse efficiency with intermittency, for more information see our factsheet on intermittency.
